I haven't compared GE in that tube type. I have GE 5Y3GT and OA3 tubes, and they have a muscular, slightly recessed high frequency sound, less open than RCA and Sylvania that I have to compare in those types.

Hipfan, I hope the Sylvainias do what you wanted. The reason I recommended getting both those and the Raytheon was that they were both cheap, and also nice revealing tubes...the Sylvania in the direction you wanted, but likely closer to the Ruby, and the Raytheon further tending to the warm. And since semantics a is a wildcard (as well as vintage and construction of the tubes), between them I figured you would likely get a fit, while having good tubes of different character you could roll if you get into that.

The ST thing is tricky, and I have not researched the real story, but I think a lot of them are made by the same people with different labels. What I find is that plate width (the inner T-part of the plate the wires goes through can be wider or narrower), whether they have an additional pair wires between the plates...and perhaps mica shape..These appear to indicate vintage, but most importantly, variations in sound.

All my STs have ribbed black plates, and I am guessing some are made by RCA (labeled Westinghouse and RCA), and one pair with the additional internal wires (labelled Raytheon and Sylvania) made by Sylvania or Raytheon???? or are they just earlier vintage RCAs????.

For mine the getter difference seems to have less sound effect than plate/mica combo...which I can't differentiate since mine have matched plate and mica structures for each of the pairs, and each pair is different from the others.

With one pair, the one with additional, central internal wires, and with medium width central part of the plate T, and with round top mica (no spurs), is the most open...closest to the Ruby sound but I think smoother. The pair with a thinner internal T part of the plates, and with round top mica with spurs, is in the middle sound-wise. And the widest central plate T (where the T "base" extends past the vertical wires that go up the plates) and with rectangular/spurred top mica, are the most liquid/warm. I can't say one is better than another, just different.

The one thing I would do, is be sure the tubes you choose are identical in structure.

I am glad you got hold of the Raytheons too. Better chances of finding synergy with two choices. Looking forward to your impressions. Lucky for us, the MkIII's adjustment switches and knobs make fine tuning to a tube easy.

Finally home from vacation and my tubes were here when I arrived. This is my first time tube rolling and I have a question. The stock Rubys have 4 pins. The Sylvania's have 8 pins and the Raytheon's have 5 pins. Is there a reason for this?

I don't know the answer to your question. Of my 5U4G-ST and 5U4GB, by far most have 5 pins. My ruby's have 4 like yours. And my current fav, some 60's Sylvania 5U4GB have 8. I have some 50's and 70's Sylvanias with 5.

my opinion so far; tesla nos and new 6922 last place.. slightly dull but tolerableelectro harmonix 6922 (shipped w)..clear concise, little thinner than thephillips ECG6922 .. great tubes lots of color and full soundtelefunken 7dj8's nos.. my fav. tight, clear, deep sound...very German precise and on point... very detailed. of course they were also the most expensivethis is fun

One thing I have noticed is that there are so many years and models of tubes from a given company, that though they do seem to tend toward general characteristic qualities, they are quite variable within that. For example, I have a pair of early 60s Telsa 6922 that sound really good to me, open and detailed but also rich, and some from the 70s I really can't get excited about.

And Phillips tubes for example, they may be made at different factories in different countries. Then there are Zaerix that are made by the big companies for Zaerix, sometimes England, Holland, Russia....whatever.

Since you like the Telefunken 7DJ8, I suspect you will like other 7DJ8s too. I think they really work well with the Torii. I must have 7 or 8 pair (including some Telefunkens) and I like them all...real, textural, and big without being too pushy. The Telefunkens are probably the most edge defined, or precise as you put it...perhaps a bit too much so for me depending on what tubes they are with. But now, with some big, warm and articulate 60s Sylvania 5U4GBs, and some warmish Amperex OA3s, they sound very good. All 7DJ8s I have excel at that indescribable "in the room" quality.

Hi I'm new to the forum and in need of some help. I've had my Torii for a few months now. I recently tried the RCA 5U4GB tall bottle as talked about on this thread. The thing is the base of the tube is too wide and the screws that hold the socket in place on the amp prevent it from completely seating and so the tubes don come on. Has anyone had this issue and what can be done about it? Thanks.

I think the easiest solution would be to gently notch out the plastic edges of the base by the screws. This had been done (not by me) on a rectifier in my Select amp years ago.Allowed the tube to seat and connect.

I think most of my rectifiers rest on the screws to various degrees and work...including the stock Rubys. Since the contacts in the sockets start working pretty soon after you start the pins into the socket (I just pulled the Sylvania 5U4GB I am using out so you could see a good 1/8-3/16" of the pins from the side, and they worked) I am wondering if your issue is something else.

Not knowing how familiar you are with tubes....I guess the RCAs have the socket guides intact? Do the soldered pin tips look smooth and without cracks? Have you cleaned the pins? A couple thoughts.